2,615 research outputs found

    Image-Processing Techniques for the Creation of Presentation-Quality Astronomical Images

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    The quality of modern astronomical data, the power of modern computers and the agility of current image-processing software enable the creation of high-quality images in a purely digital form. The combination of these technological advancements has created a new ability to make color astronomical images. And in many ways it has led to a new philosophy towards how to create them. A practical guide is presented on how to generate astronomical images from research data with powerful image-processing programs. These programs use a layering metaphor that allows for an unlimited number of astronomical datasets to be combined in any desired color scheme, creating an immense parameter space to be explored using an iterative approach. Several examples of image creation are presented. A philosophy is also presented on how to use color and composition to create images that simultaneously highlight scientific detail and are aesthetically appealing. This philosophy is necessary because most datasets do not correspond to the wavelength range of sensitivity of the human eye. The use of visual grammar, defined as the elements which affect the interpretation of an image, can maximize the richness and detail in an image while maintaining scientific accuracy. By properly using visual grammar, one can imply qualities that a two-dimensional image intrinsically cannot show, such as depth, motion and energy. In addition, composition can be used to engage viewers and keep them interested for a longer period of time. The use of these techniques can result in a striking image that will effectively convey the science within the image, to scientists and to the public.Comment: 104 pages, 38 figures, submitted to A

    Proof-to-Print Match: Effectiveness of Substrate-Corrected Colorimetric Aims in Soft Proofing

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    Soft proofing is an effective solution for clients and printers that decreases production cost and cycle time. However, print buyers are increasingly specifying brighter papers, which contain optical brightening agents (OBAs). One potential concern facing adopters of soft proofing systems is that they fail to consider the influence of OBA when rendering color images. Proofing systems are largely based on existing published specifications and their ICC profiles. These specifications and ICC profiles -- such as SWOP 3 and GRACoL 2006-- do not account for the influence of OBA-loaded printing papers, and therefore could cause a mismatch between the soft proof and the final print. To improve the soft proofing performance, it is important to account for the influence of OBA in printed color and in soft proofing. This research project investigated the use of the substrate-corrected colorimetric aims (SCCA) as the source ICC profile to improve proofing color accuracy. By conducting psychometric experiments and analyzing with Chi-Square statistic, the research concludes that (a) OBA causes the mismatch between the default soft proof and the OBA-loaded print; (b) source ICC profiles, built from both a fully characterized dataset and an SCCA solution, can improve color match between the soft proof and the OBA-loaded print; and (c) color match between the soft proof and the print is image-dependent

    Test Targets 3.0: A Collaborative effort exploring the use of scientific methods for color imaging and process control

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    Test Targets 3.0 focuses on the integration and analysis of a number of input devices, color image renderings with the use of a robust CTP system and a full-fledged web offset press … The first section is a collection of test forms … The second section is a compilation of color management practices by the class. – p. v

    Reproducing wooden and marble patterns using multi-channel ICC profile

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    Gravure can reproduce a high quality images because of its capacity to lay down ink films of variable thickness, especially for long runs and high color saturation; this aspect provides a very high shadow detail just like photograph. Many organizations have tried to standardize printing like Fogra, ISO, and more. Larger gamut are being built to cover more out-of-gamut colors, but designs, graphics and colorfulness of the products, are limited due to the involvement of several process variables. In publication printing, only four colors of ink are used: yellow, magenta, cyan, and black. CMYK primaries are generally used because the images to be printed have memory colors (blue sky, green grass) or colors that are obtainable within the CMYK gamut. ICC color management helps the user to build ICC profile is to establish which color is produced when a given combination of CMYK dots are printed. However flooring and wooden patterns printing industry, which often uses gravure printing, use non-CMYK primaries because they are better tuned to the limited color space of such patterns. To successfully reproduce these colors, a smaller or customized gamut is selected. Today proprietary software applications are being used for selection and separation of the non-CMYK primaries to obtain the smaller gamut. This research focused on new non proprietary software for selecting primaries and building multi-channel spot color ICC profiles for reproducing the marble and tile patterns

    Test Targets 4.0: A Collaborative effort exploring the use of scientific methods for color imaging and process control

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    Test Target 4.0 (TT4.0) is the result of student teamwork to publish a technical journal for a graduate-level course titled: Advance Color Management (Course no. 2081-735-03). Offered by the School of Print Media (SPM) at Rochester Institute of Technology (RIT), the course is a platform to experiment and to realize a new digital imaging paradigm and the dynamics of teamwork.... Team members learn scientific methodology in process control for repeatable color as well as apply ICC-based color management practices in digital workflows. They plan and conduct press run analyses reported in TT4.0, which is printed using facilities available at RIT. In producing this publication, the team learns to integrate design, content creation, digital media, and print production in a seamless workflow.... -p. 4

    Ecological Sustainability and Waste Paper Recycling

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    AbstractIn accordance with environmental sustainability and in order to optimize the recycling process of prints from indirect electrophotography with liquid toner the results of investigating the effects of changes in printing conditions on the characteristics of recycled fibres is presented. Changing of printing machine conditions, respecting of voltage variations, comprises of the reverse rollers and intermediate cylinder.Based on the results it can be concluded that the change in the voltage of the reverse rollers more affect the recycling efficiency with respect to the voltage change of the intermediate cylinder. Brightness gain is higher when the print for recycling is made on uncoated paper compared to coated, and dependent on the voltage changes. Effective residual ink concentration decreases far more on handsheets obtained from recycled samples on uncoated paper in relation to both sides coated paper. Increasing the positive voltage of intermediate cylinder and increasing the negative charge of reverse rollers increases the 3 D gamut CIE L*a*b* color cubic units. Guidelines for the size of the voltage in order to obtain optimal print reproduction are provided.The further research will include the development in area of clean technologies, advanced materials, closed loop systems; therefore the significant terms in the area of environmental sustainability

    Investigating the Effect of Color Gamut Mapping Quantitatively and Visually

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    With the advent of various color management standards and tools, the print media industry has seen many advancements aimed towards quantitatively and qualitatively acceptable color reproduction. This research attempts to test one of the most fundamental and integral parts of a standard color management workflow, the profile. The gamut mapping techniques implemented by the ICC profiles created using different profiling application programs were tested for their congruity to the theoretical concepts, standards, and definitions documented by International Color Consortium (ICC). Once these profiling software applications were examined, the significance of the possible discrepancies were tested by establishing a visual assessment of pictorial images using these profiles. In short, this research assessed the implementations of the ICC color rendering intents in a standard or a commonly used color managed workflow, and then described the significance of these discrepancies in terms of interoperability. For this research, interoperability was defined the assessment of different ICC profiles in producing similar results, i.e., quantitatively and visually. In order to achieve the desired assessment, the two profiling applications were selected and each used to create an output profile using the same characterization data set. The two profiles were then compared for differences in the way they mapped real world colors. The results displayed that even though there were some significant quantitative color differences, visual subjective evaluation did not reflect any noticeable color differences and therefore concluded that the profiles were interoperable. These findings reveal that even though quantitative color differences may reflect significant color differences, subjective visual comparisons may not always reflect the same or agree with quantitative findings

    Using ΔE Distribution as a predictor of digital proofing performance

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    The performance of color matching in ICC-based Color Management Systems (CMS) is being improved, and its workflow established. As part of the digital workflow, digital proofing plays an important roll in the control of color from capture to the printed page, but its method of evaluation is not clearly understood. To evaluate the degree of color matching by digital proofing in an ICC-based CMS between a reference image and a sample image, the [formula] calculated by averaging the individual color differences is being used. Doing a qualitative evaluation, ICC-based CMS should be able to stand behind the statement that the color space transformation through the Profile Connection Space (PCS) is correlated to visual judgments. The ΔE*a,b Distribution should provide more information than the average [formula] to evaluate the degree of color matching in digital proofing. In this research, the visual judgment between digital proof and a reference image color matches is studied. Using a reference image, and digital proofs as sample images, a psychometric evaluation based on the one-dimensional scaling technique is applied to scale the visual assessments. From the three dimensions: lightness, chroma, and hue; the lightness (L*) dimension was the only aspect addressed to scale the visual assessments. The reference image was generated with the color characterization data for Type 1 printing 1, and digital proofs with the input data characterization of 4-color process printing (IT8.7/3 target)2,3. Those digital proofs were presented to a panel of observers; data were collected, and analyzed to develop a preference scale that represents the qualitative evaluation of the color match. To test the accuracy of the ΔE*a,b Distribution for evaluating the degree of color matching, a quantitative analysis was done. The ΔE*a,b Distribution was analyzed by the cumulative frequency distribution technique between the reference image and the digital proofs, for 182 patches of the IT8.7/3 target, and the best critical value to match the visual scale was obtained. A quantitative evaluation between the digital proofs and the reference image, based on the color characterization data for Type 1 printing 1,4, was used to scale the average [formula] and the ΔE*a,b Distribution. Then, a classical statistical method was applied to those metric scales and to the visual scale to infer that the degree of color matching is better correlated between the visual judgement and the ΔE*a,b Distribution, than between the visual judgement and the average [formula]. Finally, using this method based on the qualitative analysis, a median of the ΔE*a,b Distribution of 52.8% would produce a visual match between the reference and the sample. Endnotes for Abstract ANSI CGATS TR 001-1995 Graphic technology - Color characterization data for Type 1 printing. ISO 12642:1997 Graphic technology - Prepress digital data exchange - Input data for characterization of 4-colour process printing. ANSI IT8.7/3. Graphic technology - Input data for characterization of 4-color process printing. Reston, Virginia. June 21 (1993). ANSI CGATS.6-1995 Graphic technology - Specifications for graphic arts printing Type 1

    Key Factors Affecting Color Reproduction On T-Shirt Fabrics Using Heat Transfer Printing

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